The present invention relates generally to free wheeling or idling pulley wheels and, more particularly, to a removable pulley wheel arrangement for use in a meat band saw wherein the pulley wheel is mounted on a shaft in a quick-release manner to permit simple removal for cleaning and replacement purposes.
In the food processing industry large upright band saws such as band saw 10 of FIG. 1 are commonly used for cutting meat products of a variety of sizes. Such band saws typically include a frame 12 upon which is mounted a support surface 14 for positioning meat products to be cut. A housing portion 16 of the frame extends above support surface 14 and a housing portion 18 of the frame extends below support surface 14. A band saw blade 20 passes though a plane defined by support surface 14 and extends around pulley wheel members 22 and 24 located within housing portions 16 and 18. Pulley wheel 24 is connected to a drive mechanism for drivingly moving the band saw blade 20 as it rotates. In particular, a drive motor may be connected for rotating pulley wheel 24. Pulley wheel 22 acts as an idler wheel, rotating freely along with the blade.
One embodiment of a prior arrangement for an idler wheel is depicted in the exploded view of FIG. 2 where idler pulley wheel 22 is mounted on the end of shaft 26. Idler wheel 22 is a unitary member with a central hub 28 which defines an opening. The interior side of the hub 28 includes a slot or keyway 30 for receiving pin extensions 32 of the shaft 26. The shaft 26 is mounted to the frame 12 for rotation via assembly 34. When the wheel 22 is positioned on the end of the shaft 26 rotation of the wheel 22 caused by movement of blade 20 likewise causes the shaft 26 to rotate via inter-engagement of the slot 30 and pin extension 32. The wheel 22 is maintained on the end of the shaft 26 using a latch mechanism which is mounted to the exterior hub 28 of the wheel. The latch mechanism includes a retaining latch 36 rotatably secured to the wheel hub via a shoulder screw 38. An outwardly biased catch 40 of the spring-loaded type is also positioned in the outer surface of the hub 28 and contacts the retaining latch 36 to hold the latch in its latching state. In this regard, when in the latching state, a portion of the retaining latch 36 sits within a groove 42 positioned toward the end of the shaft to prevent the wheel 22 from being slid off the end of the shaft. As the wheel 22 and shaft 26 rotate, the retaining latch 36 and catch 40 also rotate, with a portion of the retaining latch 36 remaining in the groove 42 during rotation.
The present invention provides a new idler pulley wheel arrangement for use in food product band saws.
In one aspect of the present invention, an idler pulley wheel arrangement for a bandsaw includes a non-rotating idler shaft and an idler pulley wheel assembly positioned on the shaft for rotation relative thereto. A latch mechanism is positioned on an end of the shaft and includes a latch part connected to the end of the shaft for movement between a first position defining a latching state of the mechanism in which a portion of the latch part extends beyond an outer surface of the shaft and a second position defining a non-latching state of the mechanism in which the latch part is positioned entirely within or in substantial alignment with the outer surface of the shaft. The latch mechanism also includes a catch positioned on the end of the shaft for holding the latch part in the non-latching state such that the idler pulley wheel assembly can be slid off the end of the shaft when the latch mechanism is in the non-latching state.
In another aspect of the invention, an idler pulley wheel arrangement for a bandsaw includes a non-rotating idler shaft and an idler pulley wheel assembly positioned on the shaft. The idler pulley wheel assembly includes a pulley wheel with a central opening, a bushing positioned within the central opening, and bearings positioned between an outer surface of the bushing and an inner surface of the pulley wheel. The pulley wheel is rotatable relative to the bushing and an inner surface of the bushing contacts an outer surface of the shaft for preventing relative rotation therebetween. A latch mechanism mounted on an end of the shaft includes a latch part connected to the end of the shaft for movement between a first position defining a latching state of the mechanism in which a portion of the latch part extends beyond an outer surface of the shaft and a second position defining a non-latching state of the mechanism in which the latch part is positioned entirely within or in substantial alignment with the outer surface of the shaft.
Still a further aspect of the invention provides a band saw apparatus including a frame, a driving pulley wheel mounted for rotation on the frame, and an idler shaft extending from the frame and spaced from the driving pulley wheel, the shaft fixed in a non-rotatable state. An idler pulley wheel assembly is positioned on the shaft for rotation relative thereto and a latch mechanism is positioned on an end of the shaft. The latch mechanism includes a latch part rotatably connected to the end of the shaft and movable between a first position defining a latching state of the mechanism in which a portion of the latch part extends beyond an outer surface of the shaft and a second position defining a non-latching state of the mechanism in which the latch part is positioned entirely within or in substantial alignment with the outer surface of the shaft, wherein the idler pulley wheel assembly can be slid off the end of the shaft when the latch mechanism is in the non-latching state.